D. seems the most probable since plastic is barely biodegradable.
The given data is Magnification, M = 15
Length of the tube , L = 16 cm
The focal length of the lens can be calculated by:
M = L/F
Substituting the value, we get:
15 = 16/f
f = 16/15
f = 1.067 cm
Using the equation of magnification we get,
M = v/u
Substituting the values we get:
15 = v/u
v = 15 u
With the help of lens formula, calculate the object distance:
1/f = 1/v + 1/u
Substituting the value we get,
1/1.067 = 1/15u + 1/u
0.937 = 1.067/u
u = 1.13 cm or 1.1 cm.
Hence, the object distance is 1.1 cm.
Answer:
C. capillaries connect arteries and veins.
Explanation:
A is false, veins carry blood towards the heart.
B is false because arteries are the thickest blood vessel.
C is completely true
D is false, heartbeat is controlled by electric impulses
Answer:
False
Explanation:
Approximately 200 out of 200 million sperms ejaculated during intercourse reach the general vicinity of the egg. They sperms must undergo capacitation during which dilute inhibitory factors fluids of the female reproductive tract weaken the membrane of the sperm head so that head of the sperm can be broken easily when it came in contact with the egg.
The first sperm to reach an egg isn’t the one to fertilize it because the egg is surrounded by a gelatinous membrane called the zona pellucida. Outside this layer, a layer of small granulosa cells also present.
Therefore, it requires numerous sperm to clear a path through these barriers before one of them can penetrate the egg and fertilize it.
Answer:
hydrogen and oxygen combine explosively in a single raction
Explanation:
The reason is Molecules of hydrogen react with oxygen violently to break the initial molecular bonds and form new one between the atoms of the two elements. The reaction results into an explosive release of energy and the production of water because the products of the reaction are at a lower energy level
